• ssh how to connect using a SOCKS 5 proxy with nc and proxycommand


    This is not about using ssh as a proxy, but rather, using a proxy when you are SSHing to another host and using ProxyCommand (where we normally use nc as our proxy tool). In newer versions of nc the syntax has changed to the following: ssh -o ProxyCommand="nc -x 127.0.0.1:1234" %h %p user@host The format must be like above in newer nc versions. Just be sure to change the 1234 to the port of your SOC........
  • chown how to change ownership on a symlink


    If you just do a normal chown user.user somedir it won't work. You will see the ownership is still the previous owner. How To Change Ownership Of Symlink: The simplest part is just adding the -h which means no dereference so it applies the ownership on the symlink and does not try (and fail) to change ownership of the dereferenced symlink destination. chown -h user.user somedir........
  • Firefox Cannot Hit Enter Key In Address Bar and Location History Not Working


    Opening Firefox from the CLI reveals the following as the cause of the error: Query failed: Error: Error(s) encountered during statement execution: no such table: moz_favicons The symptoms of this issue are that in the address bar you cannot hit enter to browse to a site/url/address and your history cannot be accessed, nor does your history show up in the address bar when typing previously used addresses. This usually happens because you've........
  • Cisco Unified Communications Manager / CUCM IP 8.6,10,12 Install Error Solution


    Install Errors on Version 12: This error happened on QEMU emulator version 2.11.1 pve-qemu-kvm_2.11.1-5 on Proxmox/Debian but installing on QEMU.12 on Centos 6 did not produce the error. *Update it is not related to the OS or QEMU version. This happened in Centos 6 too after a second install. What really causes this even though you successfully install........
  • How Does Cisco CUCM (Cisco Unified Communication Manager) Work?


    Cisco's CUCM (Cisco Unified Communication Manager) is a system that combines voice, video, data and mobile products into a single unified management suite. At its core, the CUCMis like a "Super PBX" that controls the flow of all communications through an organization even single or multiple site deployments. Cisco's CUCMmakes communication more effective and simple through centralized management and unification of communications resources.........
  • vi error solution E166: Can't open linked file for writing


    This is not so much of a vi error as it is a physical filesystem error in the sense that the file you are trying to write to is a symlink and the destination doesn't exist or for some other reason is inacessible. So vi is tellng you "you're writing to a symlinked file and the file the symlink points to cannot be written to". This is especially highlighted byt he fact that if you are using wq! to write and you still get the error.........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands


    [root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........
  • Linux How To Clone One System Harddrive to another remote system


    The easiest way is to use SSHand DD or a combination of netcat. SSHwill be a little slower due to encryption but is the most secure way (on two older systems the average clone speed is about 40-50MB/s). This is also OS independent as it doesn't matter what the source OS is because you are literallly cloning the drive so you retain the partition table and settings. Clone HDD using SSH and DD........
  • iptables v1.4.7: can't initialize iptables table `NAT': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded.


    iptables -t NAT -A PREROUTING -s 24.30.44.0/24 -j DNAT --to-destination 10.10.10.1 iptables v1.4.7: can't initialize iptables table `NAT': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. Solution # it is case sensitive "nat" and DO NOT use "NAT" or you will get this error! iptables -t nat -A PREROUTING -s 24.30.44.0/24 -j DNAT --to-destination 10.10.10.1........
  • Linux how to copy GPT partition table with dd


    The old MBR 512 bytes partition table is no longer valid if you are using GPT. To copy a GPT table with dd to another disk do it like so: Below sda is the source disk and destination disk is sdb (change to meet your needs). dd if=/dev/sda of=/dev/sdb bs=1536 count=1 You can also use dd to backup your partition table like normal but with the bs of 1536 dd........
  • phpBB3 slow and internal dummy connection


    Using Apache 2.2 and PHP5.6 PHPBB3 is very slow to respond. Actually for some reason it takes so long to even register a log entry in access_log as in several seconds or a few minutes later it shows up in Apache. All other vhosts and Apache access stops working and freezes until the request to access PHPBB3 slowly completes. It seems to randomly be slow if you stop using it whether for posting or reading the forums. I've migrated to different machines including........
  • ssh forward multiple ports in the same connection and command even works with NAT!


    You can actually just pass multiple "-L" statements to achieve this. An example is as below: ssl -L 80:192.168.10.5:80 -L443:192.168.10.5:443 -L2068:192.168.10.5:2068 -L 8192:192.168.10.5:8192 user@remotehost.com The above essentially is saying forward ports 80,443,2068,8192 to the remote IPof 192.168.10.5 (even though it is behind NAT). Essentially SSH will do the NAT part even if the........
  • iptables how to forward localhost port to remote public IP


    iptables -t nat -A OUTPUT -m addrtype --src-type LOCAL --dst-type LOCAL -p tcp --dport 3306 -j DNAT --to-destination ip.ip.ip.ip iptables -t nat -A POSTROUTING -m addrtype --src-type LOCAL --dst-type UNICAST -j MASQUERADE sysctl -w net.ipv4.conf.all.route_localnet=1 Make sure you substitute "ip.ip.ip.ip" for your real public IP and also the "--dport 3306" for the port you want to forward. Finally run the sysctl command and........
  • OpenVZ Error: Failed to load 2nd level quota solution


    Syncing private Live migrating container... Syncing 2nd level quota 11000: invalid option -- F Usage: vzdqload quotaid [-c file] commands Loads user/group qouta information from stdin into quota file. -c file use given quota file Commands specify what user/group information to load: -G grace time -U disk limits........
  • cp copy all contents of directory to another one including hidden files and folders howto


    cp -a /your/source/. /your/dest/ -a preserves all file atributes and symlinks the "." at the end of /source/ includes all hidden files such as .htacess, .bash_history, .ssh etc.. The / in /dest/ makes sure the contents go into it instead of replacing /dest itself (eg. if you did not have the / at the end).........
  • Apache SSL Reverse Proxy Very Slow Solution


    This is a simple fix but not a simple problem and it still doesn't make sense to me. But in a nutshell if your target proxy server works fast when accessing directly over SSL then this may be your issue. It seems SSL does not play nicely when the target proxy destination/host has a riduculously long key (such as 8192 bits long). Now this is normally not a problem, in fact the target server could be accessed with hardly any delay directly despite such a long key.........
  • Linux Mint/Ubuntu/Debian Dual NICs networks problem when enabling and disabling one device


    The Scenario You have dual NICs and you disable NIC1 which uses 192.168.1.1 as its gateway. With NIC2 you enable it/connect it to another network which also has the gateway 192.168.1.1 Everything will work fine at this point. When switching back to NIC1 even with NIC2 disabled and even unplugged, the OS basically can't pick up the new/updated ARP entry of the old device for 192.168.1.1 and perhaps thinks it is a security risk or spoof of some sorts and blocks i........
  • Centos installing grub problems suspect gpt problem


    grub> root (hd0,0) root (hd0,0) Filesystem type is ext2fs, partition type 0xfd grub> setup (hd0) setup (hd0) But if you do: root (hd1,0) setup (hd1) it does work, I think hd0/sda had a GPT partition that was not removed properly (what I did was just dd bs=512 count=1 the partition table from another drive since the partition table should be identical). Checking if "/boot/grub/........
  • iptables port forwarding multiple ports to another IP


    iptables -t nat -A PREROUTING -p tcp -m multiport --dports 80,443,2068,8192 -j DNAT --to-destination 192.168.1.175 Just adjust the "--dports" to the ports you need and the --to-destination to the destination IP (note it must be on the same network as the server running iptables........
  • libguestfs tools howto guide for mounting partitions and managing virtual machine images


    libguestfs tools howto guide for managing virtual machine images. libguestfs-tools aka guestfs tools has a lot of tools that make this very easy for you. You can easily mount partitons from an image with some of the commands below. To mount a partition #mount the kvmuser102821.img image and the /dev/sda1 partition from it to the local directory "mount" guestmount -a kvmuser102821.img -m /dev/sda1 mount ........
  • Openvz iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. solution


    iptables -t nat -A PREROUTING -p tcp -m tcp -d 192.168.2.1/32 --dport 3389 -j DNAT --to-destination 192.168.5.2:3389 iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. The above is often because you don't have the correct modules loaded on the hostnode or enabled for the container but in some cases it's actually a weird openvz setting. Che........
  • iptables how to forward port to another IP address with DNAT


    -A PREROUTING -d 98.98.98.5/32 -p tcp -m tcp --dport 1050 -j DNAT --to-destination 192.168.1.50:3389 The above forwards port 1050 on IP98.98.98.5 to 192.168.1.50 port 3389 (you can obviously edit things to meet your needs).........
  • iptables howto multiport forward in single line example


    -A PREROUTING -p tcp -m multiport --dports 10000,18080,13306 -j DNAT --to-destination 192.168.5.83........
  • Asterisk iptables block bruteforce attacks howto with fail2ban


    yum -y install fail2ban vi /etc/fail2ban/jail.conf [asterisk-tcp] enabled = true filter = asterisk action = iptables-multiport[name=asterisk-tcp, port="5060,5061", protocol=tcp] sendmail-whois[name=Asterisk, dest=you@example.com, sender=fail2ban@example.com] logpath = /var/log/asterisk/messages maxret........
  • iptables redirect ports to a different host and port + NAT Masquerade howto/solution


    This is important if you need public access to internal IPs such as at your office and don't want to use a VPN just to SSHinto different servers: Below forwards the port "10001" to the IP192.200.5.53 on port 22 (of course adjust it to your needs). iptables -t nat -A PREROUTING -p tcp --dport 10001 -j DNAT --to-destination 192.200.5.53:22 Remember to enable MASQUERADE on your NAT IPs or they won't be able to talk to the outside world (........
  • badblocks in Linux to check/verify if a hard drive/HDD is good or bad


    I like badblocks and don't know a better more reliable way of checking the drive. If there are no errors from badblocks and dmesg doesn't produce any SATA related errors, the drive should be good (for now at least). I also prefer to do read and write mode, yes it takes ages but it is really the best way of doing it. This gives me the most confidence in knowing that a drive, especially a new one is at least OK at the moment. To test in read only mode........
  • Thunderbird How-To Copy/Backup/Restore Accounts and Settings to Another Computer


    The best way is to use rsync, I've set it up so it doesn't copy unnecessary files, or at least ones I'm sure aren't needed. Here is the rsync command Iused (adapt to your specific Thunderbird profile location): rsync -hazv user@remotehost.com:/home/user/.thunderbird/sbrer.default/* /home/user/.thunderbird/4nyb0.default/ --exclude=global* --exclude=Cache --exclude=ImapMail --exclude=Mail This is a great way to get your e-mail accounts going on a new c........
  • KVM/QEMU Base/Template Images and the power they provide


    qemu-img create -b centos.5-8.x86.20120308.qcow2 -f qcow2 ../kvmguests/25000-centos5.8x86.qcow2 Formatting '../kvmguests/25000-centos5.8x86.qcow2', fmt=qcow2, backing_file=centos.5-8.x86.20120308.qcow2, size=10485760 kB -b the source/base image -f format is qcow2 and the location of the destination image What is so special about this? It's even quicker than creating a template with OpenVZ but this is an actual OS. It saves time a........
  • LOG: MAIN PANIC failed to expand condition "${if eq {$authenticated_id}{}{0}{${if eq {$sender_address}{$local_part@$domain}{0}{${if match{$received_protocol}{N^e?smtps?a$N}{${perl{checkbx_autowhitelist}{$authenticated_id}}}{${if eq{$received_prot


    I experienced this with CPanel's Exim after an auto-update (a Google of this error produces lots of complaints with few clear solutions). In this case I'll put the solution at the top. Run /scripts/buildeximconf to rebuild the Exim config and it should be fine after that. mail -vs "from test" user@dest.com < .bash_history LOG: MAIN cwd=/root 4 args: send-mail -i -v user@dest.com LOG: MAIN &........
  • iptables block torrents/torrenting


    This is a very basic method and won't work in all cases but will reduce the chance of torrenting/abuse by your server users. iptables -A INPUT -p tcp --destination-port 6881:6999 -j REJECT iptables -A OUTPUT -p tcp --source-port 6881:6999 -j REJECT........
  • postfix lopback error solution


    This is the mail system at host mail.postmail.com. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to If you do so, please include this problem report. You can delete your own text from the attached returned message. &........
  • Thunderbird/MBOX to IMAP/Maildir migration done easy with mb2md


    Convert MBOX Mail files into Maildir using Linux *You need perl an the TimeDate module Get the free Perl script mb2md from the project/author's site: wget http://batleth.sapienti-sat.org/projects/mb2md/mb2md-3.20.pl.gz gunzip mb2md-3.20.pl.gz #remember you need timedate or you'll get this error: ./mb2md-3.20.pl Can't locate........
  • Postfix/Any Email Server check for Open Relay


    The first thing you need to remember is not to check from the same host/server itself. This is a silly mistake I made, the reason is that many mailservers and especially postfix are configured to allow relaying from the localhost/same host. If you do that you'll get a false positive. *Make sure you test from another host/system than the mail server itself! telnet yourmailserverhost.com 25 220 Courier (FreeBS........
  • Understanding /etc/aliases from sendmail when using with postfix or other MTA's


    understanding /etc/aliases *remember to apply changes you need to run "newaliases" after editing /etc/aliases one thing I don't get is that it doesn't allow you to specify the whole e-mail address on the left-hand side eg: yourfullemail@domain.com: someotheremail@domain.com postalias: warning: /etc/aliases, line 109: name must be local (if you try the above) It works more like this: your........
  • rsync and cp doesn't/won't include .hidden files


    I was shocked that options like preserve and archive made no difference! This is a big deal and will catch people off guard. Rsync include hidden files Solution: You need to use something like: rsync -Pha /source/dir/. /dest/dir *Notice the "." at the end of the source directory. cp -a still ignores them too, the solution is the same: cp -a /source/directory/. /destination........
  • rsync preserve attributes, permissions/ownership and times without being root non-root user


    One of the purposes of rsync is to backup whole filesystems and archive them but how can you do that properly and restore things to normal if all permissions and ownerships are not preserved from your root filesystem? It's not desirable to have everything running as root, especially not just for an rsync. The Easy rsync preserve permission solution for non-root users sudo is the answer and all you have to do is edit /etc/sudoers At the end o........
  • How to chroot properly into your OS/distro


    From a LiveCD or if you're doing something like converting your non-RAID install to mdadm here's how you would chroot properly (you have to mount your proc, sys and dev on the running system/LiveCD to your chroot environment if you want things to work right, especially if you need to run update-initramfs due to a driver change etc..) *replace "path" with your mount/chroot path mount -o bind /proc /mnt/path/proc mount -o bind /dev/ mnt/pa........
  • Linux How To Add/Delete A Default Route/Gateway


    Remember to replace "eth0" with your NIC device although usually it will be eth0. Replace 192.168.1.1 with your default gateway, remember you can also add multiple gateways by adding a second/different default gateway. route Kernel IP routing table Destination Gateway Genmask&nb........
  • Openvz Live Migration Error - Error: undump failed: Invalid argument Restoring failed: Error: iptables-restore exited with 2 Error: Most probably some iptables modules are not loaded Error: rst_restore_net: -22


    Adding IP address(es): 192.168.5.8 192.168.5.9 Setting CPU units: 1000 Error: undump failed: Invalid argument Restoring failed: Error: iptables-restore exited with 2 Error: Most probably some iptables modules are not loaded Error: rst_restore_net: -22 Container start failed Stopping container ... Container was stopped Container is unmounted Error: Failed to undump VE Resuming... vzquota : (erro........
  • OpenVZ/vzctl how to do an on-line migration without downtime


    vzmigrate --online dest-host VEIDNO eg.: vzmigrate --oneline 192.168.1.55 101 One option I would recommend is "--keep-dst", that way if the migration is interrupted you can still bring the VPS back up on the original host. After the migration is successful you can manually destroy it. OpenVZ has a good writeup on this including Checkpointing and Restoring etc:........
  • email2fax and Asterisk to do eFaxing


    It's basically free bash shell script available from: http://wpkg.org/email2fax/index.php/Main_Page Make sure you have the required tools: libtiff ghostscript mpack/munpack Where you can e-mail your Asterisk box and it will fax it to the phone number in the subject line. The good news ends there, it is fairly undocumented and buggy. Take for example how the documentation mentions you can invoke from the com........
  • Windows XP How To Edit/Find Recent Documents and "File -> New" Templates to create New Word Document, Text/Notepad, Excel etc...


    All you have to do is browse to: C:Documents & SettingsYourUserName and you'll see the following: Inside "My Recent Documents" are of course shortcuts to the most recent documents you opened Inside "SendTo" is your sendto, you could edit that to Send a file to a network destination, your Flash Drive........
  • Clone any OS partition perfectly


    Clone any OS partition perfectlyIn one box I needed to copy the boot partition to another disk while retaining the MBR and other data. I simply ran this command: [code:1:1b1ff110ca]dd if=/dev/hda1 of=/dev/hdb1[/code:1:1b1ff110ca] [b:1b1ff110ca]if[/b:1b1ff110ca] = source patition [b:1b1ff110ca]of[/b:1b1ff110ca] = destination partition Here's an interesting article on it http://www.rajeevnet.com/hacks_hints/os_cl........
  • Tutorials on port upgrades


    Tutorials on port upgradesnice to see a FreeBSD forum http://www.redantigua.com/portupgrade.html http://www.onlamp.com/pub/a/bsd/2003/08/28/FreeBSD_Basics.html?page=2........
  • pound a Linux Load Balance and Reverse Proxy


    I have played around with Pound a little bit. It is a reverse proxy and load balancer in one, and it can be used as only a reverse proxy if you like. It is very simple to configure as either, and Pound even senses if one of the systems is down and stops sending requests to the dead server. It supports SSL (but passes the request to the destination server unencrypted) and even the Apache log format. Pound is very simple, fast a........
  • Nokia N97 review, feedback and complaints


    I've had an old Blackberry for a few years and I was ready to spend some serious cash on a nice Nokia. I love the idea of the Linux based Symbian S60 OS, so I was looking at phones like the E63, E71 (both are basically the same, at least CPU/screensize although E71 is thinner, has a 3MP camera, has GPS, and has dedicated buttons to adjust the volume). Then Iheard about the N97 and what a revolution it was supposed to be and it was even compared to iPhone. To........
  • LAME MP3 Encoder Segmentation Faults


    This happened on one of my Ubuntu machines where Igot some kind of segfault on line 21 from LAME at random while encoding MP3s (a second try is fine usually). I've read that it's best to compile it from source and that has solved most issues for people. Here is my preferred configure line: ./configure --enable-mp3x --with-fileio=lame --enable-debug --with-vorbis Even with that I got a different error this tim........
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